Two-way pump



D. CQHEN TWO-WAY PUMP June 10, 1958 2 Sheets-Sheet 1 Filed Nov. 21, 1955PIC-Ll OOOO INVENTOR.

DAVID COHEN HIS ATTORNEY June 10, 1958 D. COHEN 2,838,002

TWO-WAY PUMP Filed Nov. 21, 1955 2 Sheets-Sheet 2' FIG. 2.

INVENTOR. DAVID COHEN awzmw HIS ATTORNEY TWO-WAY PUMP David Cohen, St.Joseph, Mich., assignor to General Electric Company, a corporation ofNew York Application November 21, 1955, Serial No. 548,040 7 Claims.(Cl. 103-2) This invention relates to two-way pumps and moreparticularly to such pumps for use in the liquid flow system ofautomatic clothes washing machines. In certain automatic washingmachines a recirculation conduit is provided whereby the washing liquidis continuously circulated from the machine tub through the clothesbasket during the washing operation. A drain conduit is also providedwhereby the tub is emptied during the centrifugal extraction operationcustomarily following the washing operation. The switching of the flowfrom the recirculation conduit to the drain conduit, or vice versa, isaccomplished automatically by means of a suitable mechanism includedwithin the machine. Our invention is directed to an improved apparatusfor accomplishing that result, i. e. for selectively pumping the washingliquid from the tub into either the recirculation conduit or the drainconduit. However, in its broader aspects our invention is usefulgenerally in any similar flow diversion systems without being limitedsolely to laundry apparatus.

An object of my invention is to provide an improved two-way pump havingseparate valve means for governing the flow from the pump into alternateoutlet conduits depending upon the direction of rotation of the pump.

A second object is to provide an automatic clothes washing machinehaving an improved direction responsive drain and recirculation pump.

In carrying out my invention I provide a centrifugal pump having animpeller rotating within a cylindrical pump chamber. The pump isprovided with a centrally disposed inlet into the pump chamber and witha pair of outlets leading from the periphery of the chamber. Each of theoutlets is provided with a separate resilient flap-like valve foropening and closing it; and the two resilient valves are arranged sothat they are actuated alternately and separately by the flow of liquidfrom the impeller. When the impeller is rotating in one direction, oneof these valves is closed by the flow, and when the impeller is rotatingin the other direction, the other of the valves is closed. Thus,depending upon the direction of the rotation of the impeller the flow ofliquid from the pump is passed outwardly through one or the other of theoutlets but not through both.

The pump is particularly useful in a washing machine of the typeincluding washing means within a centrifugal extraction basket, both ofwhich are driven through a mechanism including a reversible drive motor.The pump can be advantageously used in such a machine to pump water fromthe tub to a recirculation conduit or to a drain conduit depending uponthe direction of rotation of the drive motor. The pump is preferablydriven directly from the drive motor, and one of its outlets isconnected to the recirculation conduit and the other to the drainconduit. Thus, upon one direction ofmotor rotation the pump is effectiveto recirculate washing liquid within the machine while the washing meansperforms a washing operation within the basket; whereas upon reis2,838,002 Patented June 10, 1958 2 verse motor rotation the pumpdischarges the washing liquid to a drain while the basket is rotated athigh speed for centrifugal extraction.

The features of my invention which I believe to be novel are pointed outwith particularity in the appended claims. The invention itself, both asto its organization and method of operation may be best understood byreference to the following description taken in conjunction with theaccompanying drawings in which:

Fig. 1 is a side elevation, with certain surfaces brokenaway andpartially in section, of an automatic clothes washing machine includingan improved drain and recirculation pump embodying my invention;

Fig. 2 is a plan view of the pump utilized in the machine of Fig. 1, theview being taken from the underside and with a portion of the pumphousing cover and impeller removed and showing the position of thevalves with the impeller at rest;

Fig. 3 is a view similar to Fig. 2 and showing the position of thevalves with the impeller rotating in one direction;

Fig. 4 is a view similar to Fig. 2 and showing the position of thevalves with the impeller rotating in the opposite direction; and v Fig.5 is a sectional view taken on the line 5-5 of Fig. 3.

Referring first to Fig. 1, there isshown an automatic clothes washer ofthe type having a rotatable clothes basket I mounted within an outerenclosing tub or container 2 which is supported within and enclosed byexterior cabinet structure 3. The cabinet structure includes a baseassembly 4- secured to the cabinet by any suitable fastening means 5.For leveling the machine, a plurality of adjustable levelling feet 6 areprovided extending through reinforcing plates 7 on the base and held byappropriate lock nuts 8. includes a top 9 having a backsplash panel 10upon which may be mounted appropriate control knobs 11 for adjusting andcontrolling the sequence of machine operations.

As shown herein, wash basket 1 is of the type adapted to contain thearticles to be laundered and a charge of washing liquid. The side wall12 of the basket is inclined upwardly and outwardly and is provided witha plurality of overflow and liquid discharge apertures 12a adjacent itsupper edge in the region of maximum diameter. The

uppermost edge of the basket is rolled inwardly at 13 and.

carries a balance ring and clothes retainer 13a preventing flotation andprojection of articles of clothing from the basket during washing andextracting operations. The washing means is shown herein in the form ofan agitator 14 having a center post 15 and a plurality of outwardlyextending, radial agitating vanes 16. The vanes 16 are joined at theirlower ends to a downwardly and outwardly flared skirt 17 as shown.

Basket 1 and agitator 14 are independently rotatable. For example, theagitator is driven with an oscillatory motion to perform the washingoperation in a substantially stationary basket; while, for extraction ofliquid from the laundry articles, the agitator and basket are rotatedtogether at a high speed. correspondingly, a central basket hub 18 issecured by an appropriate clamping means, such as 19, to a spin tube(not shown) projecting upwardly from a drivemechanism 2t). Hub 18carries basket 1 through fastening devices 21 extending through thebottom wall of the basket into a hub flange 22. In

a conventional manner, agitator 14 is driven through an.

The cabinet structure also 3 20, forming a transmission assembly, andthe driving connections therefrom to basket 1 and agitator 14 form nopart of my invention, a typical construction suitable for practice ofthe present invention is shown and described in Patent No. 2,639,618issued to J. W. McNairy on May 26, 1953, and assigned to GeneralElectric Company, assignee of the instant application.

As above indicated, the present invention is directed to that type ofwashing machine in which the washing liquid is constantly recirculatedduring the washing action. In such a recirculation system, washingliquid flows from wash basket 1 into outer tub 2 throughout the washingperiod and is pumped back into the wash basket. As a part of therecirculation system, I have shown basket 1 as including an aperture 24in the bottom wall thereof, and with an inverted conical, discharge nozzle 25, having a small port 26 through which washing liquid and smallinsoluble soil particles may pass into the outer tub 2. As shown, nozzle25 is located under skirt 17 of the agitator in an area of limitedturbulence, in which the insoluble soil particles tend to collect. Suchparticles are prevented from entering the static zone adjacent thebasket hub by means of a boot 27 extending from basket hub 18 downwardlyand outwardly to a radius approaching the radius of discharge nozzle 25.In addition to the thus described path of liquid flow from the basketinto the tub a substantial quantity of liquid is discharged through theupper apertures 22a in the basket during recirculation and washingaction.

The power source for driving basket 1 and agitator i4 shown as anelectric motor 23; and in accordance with this invention this motor isreversible, depending for example upon the relative polarities ofconnections to windings in the motor. Motor shaft 29 is connected to abidirectional centrifugal clutch assembly 3b as described in detail inthe aforementioned McNairy Patent 2,639,618. This bidirectional clutchassembly upon one direction of motor rotation transmits torque frommotor shaft 29 to a lower clutch half 31 integral with a drive pulley32. The pulley 32 drives a flexible belt 33, which in turn drives theagitator input drive pulley 34. The turning of the pulley 34 drives themechanism 2d so that it oscillates the agitator 14 within the basket.During drive through the lower clutch half 31 the upper clutch half 35remains substantially stationary. However, upon reverse rotation ofmotor shaft 29, the upper clutch half 35 is driven thereby to transmitrotation through its integral drive pulley 36 and flexible belt 37 to aninput pulley 38. This rotation of the pulley 38 drives mechanism 2% soas to effect rotation of extraction basket 1. My invention is notlimited to the particular form of drive shown since other types oftransmissions may be employed which upon one direction of motor rotationoperate agitation means within the washing receptacle and which uponreverse motor rotation drive the washing receptacle for centrifugalextraction.

For providing recirculation of Washing liquid discharged into the outertub, during the washing operation, and for disposal of the washingliquid on conclusion of the washing operation, I provide a pump assembly42 secured to the wall of the outer tub 2. This pump assembly embodiesmy invention in one preferred form thereof. The pump is driven frommotor 28 through a pump shaft 43 actuated from a motor shaft extension44 which has secured thereon a drive coupling plate 45. Thepump shafthas a similar drive plate 450 in generally aligned relationship, and thetwo drive plates are connected together by means of a flexibleconnection 46. This flexible connection is 'so constructed as totransmit driving torque from motor shaft 43 to the pump, whilepermitting relative motion of the motor with respect to the pump, as maybe caused by any vibration of the moving parts of the apparatus. In Fig.1, pump 42 is shown as having an in ,let bafiie 47 to prevent entranceof undesirably large articles into the pump.

Pump 42 discharges either through a recirculation hose or conduit 43 ora drain hose or conduit 4-9, depending upon the direction of motorrotation. As shown in Fig. i, the upper end of the recirculation conduit48 is provided with an appropriate nozzle 59 discharging into washbasket 1. The drain conduit may be provided with a goose neck 51 adaptedto rest on the upper edge of a stationary tub, drain standpi-pe, or thelike.

With the construction as thus far described, it will be understood thatwhen motor 28 rotates in a first direction, providing drive throughclutch half 31 to the agitator input pulley, the agitator is drivenwithin basket 1 to provide the desired washing action. At the same timeliquid discharges from nozzle and through overflow apertures 12 intoouter tub 2, and is recirculated by pump 42 back to basket 1. Uponconclusion of the washing operation, the direction of motor rotation isreversed, thereby providing a drive to rotate basket 1 at high speed forcentrifugal extraction. At the same time, the change in the direction ofrotation of pump 4-2 renders it effective to discharge all liquid in theouter tub through drain conduit 49.

Referring to Fig. 5, it will be noted that the pump 42 includes animpeller otl which is disposed within a suitable housing 65. Theimpeller 64) is mounted on the pump shaft 43 by means of a central hub66a and it includes a circular skirt 61 and a plurality of radialimpcller vanes 64 which extend upwardly from the skirt. T he pump shaft43 is journalled with respect to the pump housing bottom plate by meansof suitable anti-friction bearings (not shown) and appropriate sealingmeans between the shaft and the plate may be employed to prevent leakagealong the shaft. The upper or cover portion of the pump housing includesa centrally located aperture 65a which comprises the inlet to the pump.

Specifically, it comprises an axial inlet. The pump housing is mountedon the bottom of the tub 2 and the inlet 65a communicates directly withthe opening in the bottom of the tub covered by the strainer 47. Theoutlet conduits 48 and 49 into which the pump discharges are positionedwholly outside of the tub as shown. These conduits connect with the pumphousing through a laterally positioned valve chamber 66 which providesan exit from the cylindrical pump chamber section 67 of the housingwithin which the impeller 60 is mounted. When the impeller is driven bythe drive motor 28, water is centrifugally projected into the valvechamber under a substantial pressure.

As thus far described, this pump acts generally in the manner of acentrifugal pump taking in liquid through the axial inlet withtangential fiow from the impeller. Thus, if no arrangements wereemployed to control the flow the pump would tend to discharge throughboth conduits 48 and 49 at the same time.

As a significant part of my invention, I control this flow by means ofresilient flap-like valves 62 and 63 separately'mounted within the pumphousing adjacent the entrance into the conduits 48 and 49. These valvespreferably are formed of relatively thin sheets of material having athicker bead of material along one edge. As shown, valve 63 has a bead63a pivotally anchoring the valve in the housing intermediate port 68leading into conduit 48, and housing wall 69. Similarly, valve 62 has abead '70 'pivotally anchoring the valve in the housing intermediate port71 leading into conduit 49, and housing wall 72. Both valves areprovided with second edges projecting beyond the side walls of the valvechamber and into the path of liquid discharged from the cylindricalsection 67 of the pump chamber. Preferably each valve is located at restposition in a plane substantially radial with respect to the pump shaft43. Each valve is preferably formed from rubber or similar flexibleplastic-like material having sufiicient resiliency'so that theinherent'restoring action ofthe material causes the valve to assume itsnormal rest position adjacent the wall of the housing, i. 'e. its openposition, whenever the pump impeller is at rest (see Fig. 2). The topand bottom edges of each valve conveniently are of narrow cross section,thus minimizing the possibility of water-soaked lint collecting thereonand'interfering with the normal closing of the valve ports. 4

In Figs. 2, 3, and 4 there are illustrated various operating conditionsof the pump 42. Specifically, in Figs. 2, 3 and 4 the relationship ofthe pump impeller 60 and the respective valves 62 and 63 is shown forthree conditions of operation: namely, when the impeller is at rest;functioning during the washing operation; and when it is functioningduring the centrifugal extraction operation. Fig. 3 illustrates theaction of the valves when the pump is driven in a clockwise directionduring the washing or rinsing steps of operation. Liquid discharged in agenerally tangential direction from the pump chamber 67 into the valvechamber 66 exerts a pressure against valve 63, tending to hold itagainst wall 69 and adding to the inherent resilient restoring action ofthe valve material. Port 68 leading to recirculation conduit 48 thus iskept open so that liquid is recirculated from the tub 2 to the basket 1.At the same time the liquid flowing into valve chamber 66 acts againstthe free end of valve 62, bending or'flexing the valve in acounter-clockwise direction about the anchoring bead 70 and forcing thevalve into closed position with respect to port 71 and against theinherent restoring action of the valve material. The closing of port 71thus prevents flow of liquid into drain conduit 49 and also the pullingof air therefrom into the valve chamber 66. p

When the pump is driven in a counter-clockwise direction during the spinextraction step of operation, the valve positioning is as shown in Fig.-4. Liquid discharged in a generally tangential reverse direction fromthe pump chamber 67 into the valve chamber 66, exerts a pressure againstvalve 62, which has previously been restored to its rest position by itsinternal resilience when the flow of liquid as above described has beeninterrupted during the reversal of motor 28 and pump 42. Valve 62 isthen held against wall 72 with the pressure of the liquid aiding theinherent restoring action of the valve material. Port 71, leading todrainage conduit 49 thus is kept open so that the tub 2 is drained. Atthe same time the liquid flowing into the valve chamber 66 acts againstthe free edge of valve 63, bending the valve in a clockwise directionabout the anchoring head 67 and forcing the valve into closed positionwith respect to port 68 and against the inherent restoring action of thevalve material. This, of course, closes ofr the recirculation conduit.Each valve is so constructed and mounted that once the valve has startedto bend about its anchoring bead, no position of dead center is reachedand the movement of the valve proceeds promptly to its full closingposition. At the same time the movement of the valve builds up aprogressively greater restoring action which reaches a maximum when thevalve is fully closed. As a consequence of the construction described,it is not necessary to have the valves project into the orbit ofimpeller 61 in order to be mechanically actuated thereby. Generally, Iprefer to have the valves bend through an angle of about 90. In'additionI prefer to have the free edges of the valves project into the bevelededge of the pump chamber section sutficiently to provide an obstructionto the tangential flow of liquid at all times when the pump is at rest.This is clearly shown in Fig. 2.

It will be noted that in my preferred embodiment the outer wall of thevalve chamber section of the pump is provided with a small recess 73intermediate the outlet ports 68 and 71. When either of the flap valves62 and 63 is closed, its free end overlies a portion of this recess.

See Figs. 3 and 4 respectively. The purpose ofthe recess 73 is toprovide a force aiding in the opening of the previ-' ously closed valvewhen the impeller changes direction, if for some reason this valveshould not open immediately due to its own internal resilience. When theliquid begins to leave the impeller in the reverse direction, it flowsunder considerable pressure into the recess and under the free end ofthe closed valve. This provides a lifting force which aids in theopening of the valve. In fact, together with the internal resilience ofthe valve it insures that the valve is opened as the other one isclosed.

From the foregoing description, the operation of the clothes washingmachine equipped with the twoway pump becomes evident. -With the machinecontrols set for washing or rinsing, a drive to the agitation means iseffected and the pump is driven in a direction providing recirculationfrom the outer tub into the wash basket. Upon reversal of the directionof rotation of the motor, under the control of any suitable sequentialcontrol, or by manual selection of .a knob 11, the transmissionautomatically rotates the basket at high speed for centrifugalextraction, or other liquid extraction means are brought into effect,and at the same time the pump becomes effective to discharge thecontents of the outer tub to the drain.

While this invention has been described by reference to a particularembodiment thereof, it is to be understood that numerous modificationsmay be made by those skilled in the art without actually departing fromthe in-- vention. It is, therefore, the purpose of the appended claimsto cover all such equivalent variations as come within the true spiritand scope of the invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A centrifugal pump comprising a housing defining a pump chambersection and a valve chamber section, an impeller for. rotation withinsaid pump chamber section and having a discharge path into said valvechamber section, an inlet through which fluid enters said pump chambersection, two outlet ports from said valve chamber section, and twoindependently, alternately movable flap valves mounted within said valvechamber adjacent said ports and arranged to be actuated by the movementof fluid from said impeller in reverse directions to close theirrespectively associated ports, said valves being biased to flex abouttheir respective mountings to their port open positions when saidimpeller is inactive.

2. A centrifugal pump comprising a housing defining a pump chambersection and a valve chamber section, an impeller for rotation withinsaid pump chamber section and having a discharge path into said valvechamber section, an axial inlet through which fluid enters said pumpchamber section, two outlet ports from said valve chamber section inside-by-side spaced relation, and two independently alternately movableresilient flap valves mounted along one edge within said valve chambersection adjacent said outlet ports for actuation by movement of fluidfrom said impeller, said valves normally flexing about their respectivefixed edges under the restoring force of their internal resilience toassume their port open positions when said impeller is inactive, andincluding portions struck by the fluid leaving said impeller when saidimpeller is moving, whereby one of said valves is closed when saidimpeller is turning in one direction and the other is closed when saidimpeller is turning in the other direction.

3. A centrifugal pump comprising a housing defining a pump chambersection and a valve chamber section, an impeller for rotation withinsaid pump chamber section and having a discharge path into said valvechamber section, an axial inlet through which fluid enters into saidpump chamber section, two outlet ports from said valve chamber section,and two independently alternately movable flap valves mounted along oneedge within said valve chamber section adjacent said ports, each valvehaving a aeespoa second edge extending into the discharge path from saidimpeller whereby upon rotation of said impeller the fluid dischargedtherefrom acts upon the second edge of one valve to hold said valve awayfrom its associated port and upon the second edge of the other valve tomove said other valve into closing relation with its associated port,said valves being biased to flex about their respective fixed edges totheir port open positions when said impeller is inactive.

4. The combination of claim 3 including a recess in the valve chambersection of said housing, said recess being disposed between said outletports so that it is partially covered by free ends of said valves whensaid valves are closed, whereby the discharge from said impellerentering the uncovered portion of said recess provides a valve liftingforce upon reverse rotation of said impeller.

5. In a centrifugal pump, a housing defining a pump chamber section anda valve chamber section, an impeller for rotation within said pumpchamber section and having a discharge path into said vflve chambersection, an axial inlet through which fluid enters said pump chambersection, two outlet ports from said valve chamber section inside-by-side spaced relation, and means for sealing off, respectively,one of said ports on one direction of impeller rotation and the other ofsaid ports on the opposite direction of impeller rotation, said meanscomprising a pair of independently, alternately movable flap valvesmounted along one edge within said valve chamber section adjacent saidports for actuation by the movement of fluid from said impeller, each ofsaid valves having a normally open position with respect to itsassociated port and being formed of a resilient material having asufficient restoring action to move said valve about its fixed edge tosaid open position when the pressure of moving fluid is relievedtherefrom, and each including a second edge extending into the dischargepath from said impeller, whereby the movement of fluid from saidimpeller actuates said valves alternately and selectively depending uponthe direction of impeller rotation. v

6. A centrifugal pump comprising a housing defining a pumping chamber,two outlet ports from said chamber, an impeller for rotation Within saidchamber and effective centrifugally to discharge liquid into said ports,and two independently, alternately movable flap valves mounted in saidhousing and each associated with one of said ports, said valves beingarranged to be actuated by the movement of fluid from said impeller inreverse directions to close their respectively associated ports, saidvalves being biased to flex about their respective mountings to theirport open positions when said impeller is inactive. e

7. A centrifugal pump comprising a housing defining a pumping chamber,an inlet to said pumping chamber, two outlet ports from the periphery ofsaid chamber, an impeller for rotation within said chamber andeflectivecentrifiugally to discharge liquid into said ports, two independently,alternately movable flap valves each associated with one of said ports,said valves being arranged to be actuated by the movement of fluid fromsaid impeller in reverse directions to close their respectivelyassociated ports, each of said valves having an end attached to saidhousing and a free portion arranged for movement to close its associatedport, said free portions of said valves being biased to flex about therespective fixed ends of said valves to their port open positions whensaid impeller is inactive, a recess means in said housing arranged to bepartially covered by the free ends of said valves when said valves areclosed, whereby the discharge from said impeller entering the uncoveredportion of said recess means provides a valve lifting force upon reverserotation of said impeller.

References Cited in the file of this patent UNITED STATES PATENTS2,621,505 Smith Dec. 16, 1952

